Lifting lighter loads for 20 to 25 reps can build as much muscle as hoisting massive iron for fewer reps. In a recent groundbreaking study at McMaster University in Hamilton, Ontario, volunteers who did up to 25 reps—enough to grow tired—at just 30–50% of their one-rep max gained the same amount of muscle as those who did just eight to 10 reps at 75-90%.
How it works
Do this as a circuit, completing one set of each move, which you'll repeat three to four times. Or, perform all three to four full sets for each exercise before moving on to the next move. Use weights light enough to allow you to do 20 to 25 reps, or as many reps as possible.
Meet our model
Ex-Marine Chris Van Etten lost both legs to an IED explosion in Afghanistan in 2012. Just a year later, he hand-cycled the entire 26.2 miles of the Marine Corps marathon. He’s also a model in the new Jockey #ShowEm campaign.